Breaking petroleum emulsions



Patented Aug. 15, 1944 omen.

BREG PETROLEUM EMULSIONS Henry G. Berger and Paul M. Goodloe, Woodbury.

N. J., assignors to Socony-Vacuum Oil Company, Incorporated, a corporation of New York No Drawing. Application March 31, 1943,

Serial No. 481,292

8-- Claims.

tion Serial No. 391,708, filed May 3, l941, issued April 20, 1943, as Patent No. 2,317,050, accordin to which such emulsions are broken by means of a water soluble, oil insoluble mahogany sulfonate.

v Sulfonation of petroleum oils produces, as is well known, two distinct types of petroleum sulfonic acids, namely, the oil layer. or mahogany sulfonic acids, and the sludge or greensulfonic acids. Thus, when the petroleum oil is sulfohated, the mahogany acids, being oil soluble, remain in they oil and are later removed therefrom; whereas, thegreen acids, being oil insoluble, settle out with the sludge.

As a consequence, there has grown to be a well established distinction between mahogany and green acids on the basis of the preferential oil solubility and waterinsolubility of the former,

.and the oil insolubility and,water solubility of the latter.

Contrary to this well-established anduniversal opinion, it is disclosed in U. S. Patent No. 2,266,-

084, issued December .16, 1941, that by observing certain criteria, there can be produced 011 solu-- ,ble mahogany sulfonic acids which form salts that are oil insoluble and water soluble.

In breaking petroleum emulsions heretofore, it often has been proposed to use the petroleum green acids; or the sludge, containing thegreen acids; or the water soluble, oil insoluble salts of the green acids. There also have been proposals of using the green sulfonic bodies in conjunction with mahogany sulfonic bodies.

Y which this invention is concernedmay be produced by relatively-light sulfonation of petroleum oils containing a'substantial amount of cyclic hydrocarbons. Thus, by using sulfuric acid of less than oleum strength on the selected petroleum stocks, we are able to obtain the desired mahogany sulfonic acids. Inthe event that the sulfonlc acids are to be obtained from a sulfonation operation which employs multiple acid treat wherein part of the treats are of less than oleum strength, and part of the treats are with oleum,

the desired mahogany sulfonic acids can be obtained by eflecting their separation from the oil before carrying out the oleum treats.

A preferred petroleum stock for the preparation of our mahogany acids comprises Coastal or naphthenic distillates of the type used as transformer oil stocks. For instance, We have found that a. Coastal distillate, having a viscosity between about 50 and about 100 seconds Saybolt Universal viscosity at 100 F., and having a pour point below 0.0 F. before dewaxing, is highly suited for the production of the type mahogany sulfonic acids with which we are concerned.

The formation of these mahogany sulfonic acids, which are capable offorming, oil insoluble, water soluble salts, maybe further illustrated by the following specific examples:

Saybolt Univ. Sulfuric acid Property of sodi- Type oil viscosity at used in treat um sulfonate of 100 F. per bbl. oil sulio'nic acids Coastal dis- 54 to 59 sec 43lbs. of 93% acid" Highly water soltillate. (added in a uble and oil inplurality of soluble. treats). Do 54 to 59 sec 70 lbs. 98% acid Highly water sol- (added in a uble and 011 mplurality of soluble. treats). Do 72 to 79 sec 50lbs.oi 98% acid Highly water sol- (added in a uble and 011 mplurality of soluble. 1 treats).

The water soluble, oil insoluble mahogany sulfonates and the sulfonic acids from which they from those encountered in the ordinary or convention'al mahogany sulfonic acid, products, that they are best recovered from the acid treated oil stock. by means of an acid jelly. Thus, after the oil is sulfonated and settled to separate sludge, the remaining sour oil is treated with a small amount of water, for example, 1%, whereby an acid jelly is formed in the oil. This acid jelly, which contains the mahogany sulfonic acids in question, is settled and separated from the oil. After the separation, the acid jelly. is neutralized, and then, permitted to settle, whereby the neutralized mixture separates into three layers, via, a top oil layer; a middle emulsion layer; and a lower aqueous layer, containing the nates and water with a minimum amount of oil and a minor amount of salt. Since the sulfoing cylinders.

nates are to be used for breaking petroleum emulsions, the removal of oil is unnecessary, and therefore, the naphtha washing step may be eliminated.

We preferto use the mahogany sulfonates as a sodium salt. However, it is to be understood that equivalent water soluble, oil insoluble salts or derivatives, including tri-ethanolamine salts, may be used. These particular mahogany sulfonates are excellent demulsifiers when used' alone, however, they may be used, if desired, in combination with other demulsifiers, and in someinstances, certain advantages are obtained by combinations of demulsifiers. A particularly effective combination is obtained by employing a mixture of the mahogany sulfonates and salts of naphthenic acids, such as sodium or ammonium naphthenates. Our demulsifiers may be used as a water solution, or they may be used in solution in a suitable organic solvent, such as a light petroleum distillate solvent or an alcohol or a mixture of organic solvents. In this connection, it might be notel that solvent naphthas of high Kauri-' Butanol values have been found to be particularly effective solvents for our demulsifiers. Further, the use of organic solvents of low-freezing points, such as naphthas and alcohols, has an advantage over'the use of water'in that freezvigorous shakes, and allowed to standat room temperature (76 F.). Readings of the amount of clear water and of "B. S." (rag-layer) were made after 10 minutes and 45 minutes of standing. Then a sample (6.25 m1.) of the supernatant oil was removed from about the 50 ml. mark of each tube by means of a pipette, diluted with an equal volume of white gasoline and centrifuged at 1200R. P. M. for 5 minutes. Readings of per cent water and B. S. in the centrifuged samples told how clean the oil was at the time the samples were taken.

A third reading of the condition of the mixing cylinders after standing atotal of 90 minutes was recorded and a second sample of the oil layer then ground out for cleanliness. By referring to the tabulated results, it is readily apparent that the combination of this invention consistently gave the cleanest oil.

In the table below, the demulsifier is identified as relative parts of a water soluble, oil insoluble mahogany sulfonate (A) and a sulfonic acid (X, Y and Z). The acid Y corresponds to the sulfonate A, i. e.', sulfonate A was prepared by neu- ,ing difllculties during cold weather are avoided. lates.

Test data on demulsifiers Mixing cylinders aiter- I Grindout 10 min. 65 F. min. 76 F. 90 min. 76- F. 5 min. Demulsifler Treating 0 Test used ratio B B Percent Percent Percent Percent Percent Percent Percent Percent Percent Percent H1 BS Hz 13 B10 BS H10 BS 1 BS 7SA22X 1:2000 11.5 0.8 12.9 0.1 13.1 0.1 .2.0 0 1.4 0 75A-25Y 1:2000 8.0 1.0 13.8 0.2 s 14.0 0.1 0.8 0 0.6 0 75A'25Z 1:2000 13.3- 0.05 13.8 0.1 14.0 0.05 1. 6 0 1.0 0 7SA-22X 1:4000 12. O 0. 3 13. 6 0. 05 14. 0 0. 05 3. 4 0 2. 8 O 75A25Y 1:4000 12. 5 0. 5 15. 6 0. 1 15. 8 0. 1 0. 85 O 0. 65 0 75A-25Z 124000 11. 0 O. 1 12. 9 0. 05 13. 8 0. O5 3. 2 0 2. 4 0 78A-22X 118000 8. O 0. 2 918 0. 1 11. 1 0. 1 6. 4 0 4. 4 0 75A-25Y 128000 12. 0 0. 5 14. 3 0. 05 14. 8 0. 05 l. G 0 1. 0 0 75A-25Z 1:8000 6. 0 ll. 2 0. 05 14. O 0. 05 5. 4 0

' We have found that demulsifying properties of We claim:

the sulfonates described above is greatly enhanced 'by use thereof in combination with sulfonic acids of the type from which the suitenates are derived, that is, mahogany vsulfonic acids whose salts are water soluble and oil insoluble.

pared either by partial neutralization of a suitablesulfonic acid mixture or the sulfonic acids may be divided into two parts, one of which is neutralized and the two portions blended in desired proportiins after formation of sulfonates from one portion.

The advantages of the present invention are demonstrated ,by tests in breaking an Illinois crude emulsion at 66F.

The tests were carried out. in the following manner: accurately measured quantities of dilute solutions of the demulsifiers were pipetted into labelled, glass-stoppered, 100ml. graduated mix- Then, as rapidly as possible, all cylinders were filled to the 100 ml. mark by de-- cantation from a large pitcher of the emulsion. The containers were stoppered, each given 1. The process of breaking petroleum emulsions of the water-in-oil type, which comprises treating the emulsion with a water soluble, oil

insoluble mahogany sulfonate and a mahogany Preferably, the acid used is substantially the same as the acid from which the sulfonate is derived. The preferred mixtures may be pre-' sulfonic acidwhich forms water soluble, oil insoluble mahogany sulfonates, said acid being present in suflicient quantity relative to said sulionate to substantially enhance the demulsifier effect of the latter.

2, The process of breaking petroleum emulsions of the water-in-oil-type, which comprises treating the emulsion with a mahogany sulfonic 4. A demulsifier for petroleum emulsions of the water-in-oil type which comprises a mahogany sulfonic acid which forms water soluble, oil insoluble sulfonates and a water soluble sulfonate of said acid, said acid being present in sumcient quantity relative to said sulfonate to substantially enhance the demulsifier eflect of the latter.

5. The process of breaking petroleum emulsions of the water-in-oil type, which comprises treating the emulsion with a solution in an organic liquid solvent having a low freezing point I of a water soluble, oil insoluble mahogany sulof a mahogany sulfonic acid which forms water soluble, oil insoluble sulfonates and a water soluble sulfonate of said acid, said acid being present in sumcient quantity relative to said sulfonate to substantially enhance effect of the latter.

7. A demulsifier for petroleum emulsions of the water-in-oil type which comprises a solution in an organic liquid s olvnt having a low freezing point of a water soluble, oil insoluble mahogany sulfonate and a mahogany sulfonic acid which forms water soluble, oil insoluble mahogany sulfonates, said acid being present in sufficient quantity relative to said sulfonate to substantially enhance the demulsifler effect of the latter.

8. A demulsifier for petroleum emulsions of the water-in-oil type which comprises a solution in an organic, liquid solvent having a low freezing point of a mahogany sulfonic acid which forms water soluble, oil insoluble sulfonates and a water soluble sulfonate of said acid, said acid being present in sufiicient quantity relative to said sulfonate to substantially enhance the demulsifier efiect of the latter.

HENRY G. BERGER. PAUL M GOODLOE.

the demulsifler 

